Mooring lines, slings, cables, and ropes are sometimes used in extreme wear conditions and must be protected. Slings, for example, are used in many forms as a support for equipment, objects, or other heavy loads used underwater, as in underwater oil rigs that need to be emplaced, removed, or moved from one location to another. These slings may be attached to heavy-duty cables that are secured to a winch or crane. The cables and slings are used to lift and support the object for transport. The slings are sometimes provided with protective covers to prevent damage by abrasion, barnacles, chemicals, salt water, etc. The covers are conventionally attached to slings with hook and loop fasteners.
In some cases, the slings are left with the object at a location, for retrieval and use at a later time. Offshore mining operations use this strategy by leaving equipment, along with the slings that carried the equipment, on the ocean floor for later use or inspection. When the equipment is due for inspection, or in need of replacement, the cables are lowered to the desired equipment and attached to the slings. The equipment is then lifted to the surface for inspection. The slings themselves are also inspected and replaced as needed. The process is similar for underground mining operations, industrial manufacturing operations, or other situations where it is efficient to leave a sling with the object.
To ensure the sling is not used beyond its useful life, the cover must be removed and the sling inspected as often as practicable. A thorough inspection may involve a review of the exterior and interior surfaces, cable attachments, closure mechanisms and general condition of the cover. Thus, the use of hook and loop re-closable closures or fasteners, may help minimize cover replacement costs. For heavy duty operations, such as the offshore mining operations described above, this cost savings could be significant. Ships, airplanes, and heavy vehicles also utilize mooring lines, cables, ropes, and the like in conditions of extreme wear and must be similarly protected.